MRI quantitative myocardial perfusion with compartmental analysis: a rest and stress study.

abstract：:A new NMR imaging technique, aiming at a reduction of the data acquisition time, is described in detail. The method is applicable in all multidimensional imaging situations where at least one spatial coordinate is resolved. Discussed at some length are the point-spread function, the required bandwidth of the NMR spect...

journal_title：Magnetic resonance in medicine

authors： van Uijen CM,den Boef JH,Verschuren FJ

更新日期：1985-06-01 00:00:00

abstract：:Activity-induced manganese-dependent contrast (AIM) MRI is a hemodynamic-independent functional MRI method that used manganese ion as an MR-detectable contrast agent. In AIM, MnCl(2) is infused intra-arterially after the blood-brain barrier (BBB) is opened with a hyperosmolar agent. Upon functional stimulation of the ...

journal_title：Magnetic resonance in medicine

authors： Aoki I,Tanaka C,Takegami T,Ebisu T,Umeda M,Fukunaga M,Fukuda K,Silva AC,Koretsky AP,Naruse S

更新日期：2002-12-01 00:00:00

abstract：:Cortical spreading depression (CSD) was visualized using manganese-enhanced MRI (MEMRI) following topical application of KCl to the exposed rat cortex. MEMRI signal increase in the ipsilateral cortex relative to the contralateral control region was 60 +/- 30% following two KCl applications. MEMRI signal increase for a...

journal_title：Magnetic resonance in medicine

authors： Henning EC,Meng X,Fisher M,Sotak CH

更新日期：2005-04-01 00:00:00

abstract：:To enhance contrast between flow and static tissue, NMR projective angiographic methods usually require data subtraction, or alternatively the application of special data processing routines such as the "maximum intensity projection" algorithm. We have successfully developed a direct projection method which yields suf...

journal_title：Magnetic resonance in medicine

authors： Matsuda T,Doyle M,Pohost GM

更新日期：1991-04-01 00:00:00

abstract：:The purpose of this study is (1) to determine the correlation between T(1rho) and T(2) and degenerative grade in intervertebral discs using in vivo 3.0-T MRI, and (2) to determine the association between T(1rho) and T(2) and clinical findings as quantified by the SF-36 Questionnaire and Oswestry Disability Index. Sixt...

journal_title：Magnetic resonance in medicine

authors： Blumenkrantz G,Zuo J,Li X,Kornak J,Link TM,Majumdar S

更新日期：2010-05-01 00:00:00

abstract：:Introduction of a Gaussian weighting function into the phase encoding of the spin-echo imaging method via variable tip angle excitation, with concomitant optimization of the recycle delay, is shown to increase the sensitivity of T2-weighted imaging by up to 40%. In addition, the Gibbs artifact associated with sharp bo...

journal_title：Magnetic resonance in medicine

authors： Webb AG,Clarkson RB

更新日期：1991-10-01 00:00:00

abstract：PURPOSE:The feasibility of imaging musculoskeletal fibrous tissue components, such as menisci, ligaments, and tendons, with a conventional spoiled gradient echo technique is explored in vivo at 3 T and 7 T. METHODS:To this end, the echo time (TE1 ) of a conventional Fourier-encoded multicontrast three-dimensional SGPR...

journal_title：Magnetic resonance in medicine

authors： Deligianni X,Bär P,Scheffler K,Trattnig S,Bieri O

更新日期：2013-11-01 00:00:00

abstract：PURPOSE:Real-time assessment of ventricular volumes requires high acceleration factors. Residual convolutional neural networks (CNN) have shown potential for removing artifacts caused by data undersampling. In this study, we investigated the ability of CNNs to reconstruct highly accelerated radial real-time data in pat...

journal_title：Magnetic resonance in medicine

authors： Hauptmann A,Arridge S,Lucka F,Muthurangu V,Steeden JA

更新日期：2019-02-01 00:00:00

abstract：:We have developed a method for measuring the electrocardiogram (ECG) continuously during MR examinations. In contrast to ECG acquisition by wires, our new method is to amplify and convert the ECG into an optical signal directly above the patient's heart. The optical signal is transmitted out of the magnet bore by opti...

journal_title：Magnetic resonance in medicine

authors： Felblinger J,Lehmann C,Boesch C

更新日期：1994-10-01 00:00:00

abstract：:Diffusion tensor imaging enables in vivo investigation of tissue cytoarchitecture through parameter contrasts sensitive to water diffusion barriers at the micrometer level. Parameters are derived through an estimation process that is susceptible to noise and artifacts. Estimated parameters (e.g., fractional anisotropy...

journal_title：Magnetic resonance in medicine

authors： Lauzon CB,Crainiceanu C,Caffo BC,Landman BA

更新日期：2013-03-01 00:00:00

abstract：:Diffusion tensor imaging (DTI) is a new imaging modality that can provide unique information on brain white matter anatomy. Measurements of water diffusion constant along multiple axes are fitted to a tensor model, from which the diffusion anisotropy and dominant fiber orientation can be estimated. Even though the ten...

journal_title：Magnetic resonance in medicine

authors： Zhang J,van Zijl PC,Mori S

更新日期：2006-02-01 00:00:00

abstract：PURPOSE:To obtain whole-brain high-resolution T2 maps in 2 minutes by combining simultaneous multislice excitation and low-power PINS (power independent of number of slices) refocusing pulses with undersampling and a model-based reconstruction. METHODS:A multi-echo spin-echo sequence was modified to acquire multiple s...

journal_title：Magnetic resonance in medicine

authors： Hilbert T,Schulz J,Marques JP,Thiran JP,Krueger G,Norris DG,Kober T

更新日期：2019-12-01 00:00:00

abstract：:Measuring T(2) at 7.0 T is not trivial due to RF inhomogeneity effects, however, gradient echo sampling of a spin echo is insensitive to RF pulse errors, does not suffer from significant distortions, and allows T'(2) and T(2) to be estimated simultaneously. Gradient echo sampling of a spin echo results are relatively ...

journal_title：Magnetic resonance in medicine

authors： Cox EF,Gowland PA

更新日期：2010-11-01 00:00:00

abstract：:The resolution in conventional BOLD FMRI is considerably lower than can be achieved with other MRI methods, and is insufficient for many important applications. One major difficulty in robustly improving spatial resolution is the poor image quality in BOLD FMRI, which suffers from distortions, blurring, and signal dro...

journal_title：Magnetic resonance in medicine

authors： Miller KL,Smith SM,Jezzard P,Pauly JM

更新日期：2006-01-01 00:00:00

abstract：:This paper describes a method for correcting the chemical-shift artifacts in 19F NMR imaging of perfluoroctylbromide emulsion (PFOB) by utilizing the two spectral peaks of PFOB which have a long T2 value in conjunction with the Dixon method. Corrected images are obtained from the magnitude of the measured images using...

journal_title：Magnetic resonance in medicine

authors： Lee HK,Nalcioglu O,Buxton RB

更新日期：1992-02-01 00:00:00

abstract：:In vivo effective relaxation rates in normal rat liver were evaluated for four dextran coated iron oxide agents: monocrystalline iron oxide nanocolloid (MION) with a mean particle diameter of 3.9 nm, a polycrystalline agent (PION) with a larger mean diameter of 12 nm, and these two agents labeled with the asialofetuin...

journal_title：Magnetic resonance in medicine

authors： Mandeville JB,Moore J,Chesler DA,Garrido L,Weissleder R,Weisskoff RM

更新日期：1997-06-01 00:00:00

abstract：:Quantitative diffusion measurements were performed in tumors arising from inoculation of nude mice with two human breast cancer cell lines (MCF7 and T47D) to evaluate the specificity of this technique for characterizing solid tumors. ADC maps were compared to histology and correlated well with gross tumor morphology. ...

journal_title：Magnetic resonance in medicine

authors： Maier CF,Paran Y,Bendel P,Rutt BK,Degani H

更新日期：1997-04-01 00:00:00

abstract：:An automatic fMRI protocol for the investigation of the human auditory cortex has been developed. For the activation of the auditory system, the scanner noise itself is the source of sound. Rapid switching of B0 gradients allows the generation of tones of defined frequencies and amplitude on a conventional scanner wit...

journal_title：Magnetic resonance in medicine

authors： Bilecen D,Radü EW,Scheffler K

更新日期：1998-12-01 00:00:00

abstract：PURPOSE:Fourier decomposition (FD) is a noninvasive method for assessing ventilation and perfusion-related information in the lungs. However, the technique has a low signal-to-noise ratio (SNR) in the lung parenchyma. We present an approach to increase the SNR in both morphological and functional images. METHODS:The d...

journal_title：Magnetic resonance in medicine

authors： Corteville DM,Kjïrstad Å,Henzler T,Zöllner FG,Schad LR

更新日期：2015-05-01 00:00:00

abstract：PURPOSE:To model and correct the dephasing effects in the gradient-echo signal for arbitrary RF excitation pulses with large flip angles in the presence of macroscopic field variations. METHODS:The dephasing of the spoiled 2D gradient-echo signal was modeled using a numerical solution of the Bloch equations to calcula...

journal_title：Magnetic resonance in medicine

authors： Soellradl M,Lesch A,Strasser J,Pirpamer L,Stollberger R,Ropele S,Langkammer C

更新日期：2020-08-01 00:00:00

abstract：:High permittivity "dielectric pads" have been shown to increase image quality at high magnetic fields in regions of low radiofrequency transmit efficiency. This article presents a series of electromagnetic simulations to determine the effects of pad size and geometry, relative permittivity value, as well as thickness ...

journal_title：Magnetic resonance in medicine

authors： Teeuwisse WM,Brink WM,Haines KN,Webb AG

更新日期：2012-04-01 00:00:00

abstract：PURPOSE:A direct method of imaging neural activity was simulated to determine typical signal sizes. METHODS:An active bidomain finite-element model was used to estimate approximate perturbations in MR phase data as a result of neural tissue activity, and when an external MR electrical impedance tomography imaging curr...

journal_title：Magnetic resonance in medicine

authors： Sadleir RJ,Fu F,Chauhan M

更新日期：2019-01-01 00:00:00

abstract：PURPOSE:Previous studies have associated low pH in intervertebral discs (IVDs) with discogenic back pain. The purpose of this study was to determine whether quantitative CEST (qCEST) MRI can be used to detect pH changes in IVDs in vivo. METHODS:The exchange rate ksw between glycosaminoglycan (GAG) protons and water pr...

journal_title：Magnetic resonance in medicine

authors： Zhou Z,Bez M,Tawackoli W,Giaconi J,Sheyn D,de Mel S,Maya MM,Pressman BD,Gazit Z,Pelled G,Gazit D,Li D

更新日期：2016-12-01 00:00:00

abstract：PURPOSE:To develop a novel, simultaneous multislice reconstruction method that exploits Hankel subspace learning (SMS-HSL) for aliasing separation in the slice direction. METHODS:An SMS signal model with the Hankel-structured matrix was proposed. To efficiently suppress interslice leakage artifacts from a signal subsp...

journal_title：Magnetic resonance in medicine

authors： Park S,Park J

更新日期：2017-10-01 00:00:00

abstract：:A magnetic resonance imaging (MRI) method is presented to detect, localize, and quantify myocardial kinematics by measuring the material rate-of-strain tensor at each pixel in gated NMR images of the heart. The immediate, local effect of muscular activity is self-deformation, and the strain tensor is the basic mathema...

journal_title：Magnetic resonance in medicine

authors： Wedeen VJ

更新日期：1992-09-01 00:00:00

abstract：:Two single-shot volume imaging techniques are described. The first, single-echo echo-volume imaging, is essentially the echo-volume imaging (EVI) sequence suggested by Mansfield (J. Phys. C. 10, L55 (1977)). The second is a multi-spin-echo approach in which one plane of k-space is collected during each spin echo. In b...

journal_title：Magnetic resonance in medicine

authors： Song AW,Wong EC,Hyde JS

更新日期：1994-11-01 00:00:00

abstract：:Single-slab 3D turbo/fast spin echo (SE) imaging with very long echo trains was recently introduced with slab selection using a highly selective excitation pulse and short, nonselective refocusing pulses with variable flip angles for high imaging efficiency. This technique, however, is vulnerable to image degradation ...

journal_title：Magnetic resonance in medicine

authors： Park J,Mugler JP 3rd,Hughes T

更新日期：2009-10-01 00:00:00

abstract：PURPOSE:Gradient imperfections remain a challenge in MRI, especially for sequences relying on long imaging readouts. This work aims to explore image reconstruction based on k-space trajectories predicted by an impulse response model of the gradient system. THEORY AND METHODS:Gradient characterization was performed twi...

journal_title：Magnetic resonance in medicine

authors： Vannesjo SJ,Graedel NN,Kasper L,Gross S,Busch J,Haeberlin M,Barmet C,Pruessmann KP

更新日期：2016-07-01 00:00:00

abstract：:Lower extremity peripheral vein bypass grafts (LE-PVBG) imaged with high-resolution black blood three-dimensional (3D) inner-volume (IV) fast spin echo (FSE) MRI at 1.5 Tesla possess a two-layer appearance in T1W images while only the inner layer appears visible in the corresponding T2W images. This study quantifies t...

journal_title：Magnetic resonance in medicine

authors： Mitsouras D,Owens CD,Conte MS,Ersoy H,Creager MA,Rybicki FJ,Mulkern RV

更新日期：2009-09-01 00:00:00

abstract：:A kinetic analysis of water signal intensity changes measured in human visual cortex by PRESS localized 1H spectroscopy at 500 ms resolution with light-emitting diode (LED) goggle stimulation was used to determine vascular transit times for transitions between rest and activation. Monoexponential curve fitting was use...

journal_title：Magnetic resonance in medicine

authors： Detre JA,Wang Z,Stecker MM,Zimmerman RA

更新日期：1995-09-01 00:00:00